I have a Mint that I bought and used for a year or so. It gets things aligned very well, but it take a while to get things correct. It takes me, by far, the longest to align a cartridge with the Mint that any other I have ever used. Meaning it takes a long time to get it set up just perfect. It's not difficult just time consuming.
Eventually I bought a Feickert protractor to try. Surprisingly it took me less than 10 minutes to align my cart, so quick that I really didn't believe that it could be accurate. Pulled out my Mint and it was spot on. So plus one for the Feickert.
Fast forward a few years later and I bought a new tonearm and turntable, used the Feickert to setup the cart and found it just as easy and fast, have changed carts a few times and it was always quick and easy to get it properly aligned. Two months ago I decided to get another Mint (better to have more than one way to verify the carts alignment, I'm thinking) made for my table and arm. After I got the Mint I put it on my table and put the cart down on it that was aligned 4 months prior with the Feickert and the cart was perfectly aligned on the Mint protractor. Didn't have to tough or adjust a thing.
So at this point I would say to just buy the Feickert and use it correctly and you will be just as good as if you had bought the Mint (or any other protractor).
YMMV.